From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Alain Knaff , Yinghai Lu , "H. Peter Anvin" , Andrew Morton , Linus Torvalds Subject: [PATCH 3.10 42/50] decompress_bunzip2: off by one in get_next_block() Date: Sun, 25 Jan 2015 10:07:32 -0800 Message-Id: <20150125180704.994315210@linuxfoundation.org> In-Reply-To: <20150125180702.521559311@linuxfoundation.org> References: <20150125180702.521559311@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter commit b5c8afe5be51078a979d86ae5ae78c4ac948063d upstream. "origPtr" is used as an offset into the bd->dbuf[] array. That array is allocated in start_bunzip() and has "bd->dbufSize" number of elements so the test here should be >= instead of >. Later we check "origPtr" again before using it as an offset so I don't know if this bug can be triggered in real life. Fixes: bc22c17e12c1 ('bzip2/lzma: library support for gzip, bzip2 and lzma decompression') Signed-off-by: Dan Carpenter Cc: Alain Knaff Cc: Yinghai Lu Cc: "H. Peter Anvin" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- lib/decompress_bunzip2.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/lib/decompress_bunzip2.c +++ b/lib/decompress_bunzip2.c @@ -184,7 +184,7 @@ static int INIT get_next_block(struct bu if (get_bits(bd, 1)) return RETVAL_OBSOLETE_INPUT; origPtr = get_bits(bd, 24); - if (origPtr > dbufSize) + if (origPtr >= dbufSize) return RETVAL_DATA_ERROR; /* mapping table: if some byte values are never used (encoding things like ascii text), the compression code removes the gaps to have fewer